Power amplifier module

ABSTRACT

A power amplifier module includes an output-stage amplifier, a driver-stage amplifier, an input switch, an output switch, an input matching circuit, an inter-stage matching circuit, an output matching circuit, and a control circuit. The input switch selectively connects one of a plurality of input signal paths to an input terminal of the driver-stage amplifier. The output switch selectively connects one of a plurality of output signal paths to an output terminal of the output-stage amplifier. The control circuit controls operations of the driver-stage amplifier and the output-stage amplifier. The input switch, the output switch, and the control circuit are integrated into an IC chip. The control circuit is disposed between the input switch and the output switch.

CROSS REFERENCE TO RELATED APPLICATION

This a continuation of U.S. Ser. No. 16/418,117 filed on May 21, 2019,which is a continuation of U.S. Ser. No. 15/944,138 filed on Apr. 3,2018, which claims priority from Japanese Patent Application No.2017-075550 filed on Apr. 5, 2017. The content of these applications areincorporated herein by reference in its entirety.

BACKGROUND

The present disclosure relates to a power amplifier module. Inaccordance with high-density mounting of components in mobilecommunication terminals, such as cellular phones, various components,such as an antenna switch, an input switch, an output switch, aduplexer, a power amplifier, a low-noise amplifier, and a matchingcircuit, are more likely to be surface-mounted on the same wiringsubstrate. Japanese Unexamined Patent Application Publication No.2014-207252 discloses a power amplifier module including a poweramplifier, a control circuit, and an output switch mounted therein. Thecontrol circuit controls the operation of the power amplifier. Theoutput switch selectively connects one of plural output signal paths tothe output terminal of the power amplifier.

BRIEF SUMMARY

In an example of the power amplifier module of the related art, however,various individual components mounted on a wiring substrate areseparately connected to the wiring substrate, thereby making wiringconnection complicated. Additionally, high-density mounting of variouscomponents on the wiring substrate may cause electromagnetic couplingbetween the components, which makes it difficult to secure isolationbetween an input signal and an output signal.

In view of this background, the present disclosure eliminates the needto perform wiring connecting operation separately for individualcomponents and also secures a sufficient level of isolation between aninput signal and an output signal.

According to embodiments of the present disclosure, there is provided apower amplifier module including an output-stage amplifier, adriver-stage amplifier, an input switch, an output switch, an inputmatching circuit, an inter-stage matching circuit, an output matchingcircuit, and a control circuit. The driver-stage amplifier is connectedto an input side of the output-stage amplifier. The input switchselectively connects one of a plurality of input signal paths to aninput terminal of the driver-stage amplifier. The output switchselectively connects one of a plurality of output signal paths to anoutput terminal of the output-stage amplifier. The input matchingcircuit connects the input switch and the driver-stage amplifier. Theinter-stage matching circuit connects the driver-stage amplifier and theoutput-stage amplifier. The output matching circuit connects theoutput-stage amplifier and the output switch. The control circuitcontrols operations of the driver-stage amplifier and the output-stageamplifier. The input switch, the output switch, and the control circuitare integrated into an integrated circuit (IC) chip. The control circuitis disposed between the input switch and the output switch.

According to embodiments of the present disclosure, it is possible toeliminate the need to perform wiring connecting operation separately forindividual components and also to secure a sufficient level of isolationbetween an input signal and an output signal.

Other features, elements, characteristics and advantages of the presentdisclosure will become more apparent from the following detaileddescription of embodiments of the present disclosure with reference tothe attached drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 illustrates the configuration of a power amplifier moduleaccording to a first embodiment;

FIG. 2 illustrates the layout of individual components forming the poweramplifier module according to the first embodiment;

FIG. 3 illustrates the positional relationship of ground surfaces and aground layer to the other components of the power amplifier moduleaccording to the first embodiment;

FIG. 4 illustrates the layout of individual components forming a poweramplifier module according to a second embodiment;

FIG. 5 illustrates the positional relationship of a ground surface and aground layer to the other components of the power amplifier moduleaccording to the second embodiment;

FIG. 6 illustrates the layout of individual components forming a poweramplifier module according to a third embodiment;

FIG. 7 illustrates the layout of individual components forming a poweramplifier module according to a fourth embodiment;

FIG. 8 illustrates the layout of individual components forming a poweramplifier module according to a fifth embodiment;

FIG. 9 illustrates the layout of individual components forming a poweramplifier module according to a sixth embodiment;

FIG. 10 illustrates the configuration of a power amplifier moduleaccording to a seventh embodiment; and

FIG. 11 illustrates the layout of individual components forming thepower amplifier module according to the seventh embodiment.

DETAILED DESCRIPTION

Embodiments of the disclosure will be described below with reference tothe accompanying drawings. The same element or the same member indifferent embodiments is designated by like reference numeral, and thesame explanation thereof will not be repeated.

FIG. 1 illustrates the configuration of a power amplifier module M1according to a first embodiment. The power amplifier module M1 is aradio-frequency (RF) module used in a mobile communication terminal,such as a cellular phone, and amplifies power of an input signal to alevel high enough to be transmitted to a base station. The input signalis an RF signal modulated by a radio frequency integrated circuit(RFIC), for example, according to a predetermined communication method.

The power amplifier module M1 includes a driver-stage amplifier PA1, anoutput-stage amplifier PA2, an input switch SW1, an output switch SW2,an input matching circuit MN1, an inter-stage matching circuit MN2, anoutput matching circuit MN3, and a control circuit CU. The driver-stageamplifier PA1 is connected to the input side of the output-stageamplifier PA2. The input switch SW1 includes plural input terminals P11and P12 and an output terminal P13. The input switch SW1 selectivelyestablishes a signal path between one of the plural input terminals P11and P12 and the output terminal P13. The input terminals P11 and P12 arerespectively connected to input signal paths Sin1 and Sin2. The outputterminal P13 is connected to an input terminal P21 of the driver-stageamplifier PA1. The input switch SW1 selectively connects one of theinput signal paths Sin1 and Sin2 to the input terminal P21 of thedriver-stage amplifier PA1. The driver-stage amplifier PA1 amplifies anRF signal input from the input terminal P21 and outputs the amplified RFsignal from an output terminal P22. The RF signal is then input into aninput terminal P31 of the output-stage amplifier PA2. The output-stageamplifier PA2 then amplifies the RF signal input from the input terminalP31 and outputs the amplified RF signal from an output terminal P32.

The output switch SW2 includes an input terminal P41 and plural outputterminals P42, P43, P44, and P45. The output switch SW2 selectivelyestablishes a signal path between the input terminal P41 and one of theplural output terminals P42, P43, P44, and P45. The input terminal P41is connected to the output terminal P32 of the output-stage amplifierPA2. The output terminals P42, P43, P44, and P45 are respectivelyconnected to output signal paths Tx1, Tx2, Tx3, and Tx4. The outputswitch SW2 selectively connects one of the plural output signal pathsTx1, Tx2, Tx3, and Tx4 to the output terminal P32 of the output-stageamplifier PA2. In this manner, the RF signal input into the poweramplifier module M1 via one of the plural input signal paths Sin1 andSin2 is amplified and is then output from one of the plural outputsignal paths Tx1, Tx2, Tx3, and Tx4.

The input matching circuit MN1 connects the input switch SW1 and thedriver-stage amplifier PA1 so as to perform impedance matchingtherebetween. The inter-stage matching circuit MN2 connects thedriver-stage amplifier PA1 and the output-stage amplifier PA2 so as toperform impedance matching therebetween. The output matching circuit MN3connects the output-stage amplifier PA2 and the output switch SW2 so asto perform impedance matching therebetween. The control circuit CUcontrols the operations of the input switch SW1, the output switch SW2,the driver-stage amplifier PA1, and the output-stage amplifier PA2. Forexample, the control circuit CU controls the bias points of thedriver-stage amplifier PA1 and the output-stage amplifier PA2 andcontrols the switching operations of the input switch SW1 and the outputswitch SW2.

FIG. 1 merely illustrates the relationships concerning the connectingstate among the components forming the power amplifier module M1.However, FIG. 1 does not illustrate the positional relationships amongthe components according to the actual layout. For the sake ofrepresentation, two stages of amplifiers are shown, but three or morestages of amplifiers may be connected to each other.

FIG. 2 illustrates the layout of the individual components forming thepower amplifier module M1. The components are disposed on a substrate100. The substrate 100 is also called a wiring substrate or a mountingsubstrate. The input switch SW1, the output switch SW2, and the controlcircuit CU are integrated into a single integrated circuit (IC) chip C1.The input switch SW1 is disposed in a region 10, the output switch SW2is disposed in a region 20, and the control circuit CU is disposed in aregion 30. The control circuit CU is disposed between the input switchSW1 and the output switch SW2. The driver-stage amplifier PA1 and theoutput-stage amplifier PA2 are integrated into a single IC chip C2. Theinput matching circuit MN1 and the inter-stage matching circuit MN2 aredisposed in a region 40. The output matching circuit MN3 is disposed ina region 50. The IC chips C1 and C2 are formed in a shape having foursides (quadrilateral, such as a substantially rectangle or square), asviewed from a direction substantially perpendicular to the mountingsurface of the substrate 100. For the sake of representation, the wiringfor connecting each of the IC chips C1 and C2, the input matchingcircuit MN1, the inter-stage matching circuit MN2, and the outputmatching circuit MN3 is not shown.

The IC chip C2 is disposed between the input matching circuit MN1 andthe inter-stage matching circuit MN2 (region 40) and the output matchingcircuit MN3 (region 50). For the sake of description, the direction inwhich the input switch SW1 (region 10), the control circuit CU (region30), and the output switch SW2 (region 20) are arranged will be calledan arrangement direction D1. Among the four sides of the IC chip C2, theside substantially parallel with the arrangement direction D1 andpositioned most closely to the IC chip C1 will be called a side L1.Among the four sides of the IC chip C2, the side positioned most closelyto the input matching circuit MN1 and the inter-stage matching circuitMN2 (region 40) will be called a side L2. Among the four sides of the ICchip C2, the side positioned most closely to the output matching circuitMN3 (region 50) will be called a side L3. The sides L2 and L3 opposeeach other with the side L1 interposed therebetween. That is, thearrangement direction of the input matching circuit MN1 and theinter-stage matching circuit MN2 (region 40), the IC chip C2, and theoutput matching circuit MN3 (region 50) is parallel with the arrangementdirection D1. Among the four sides of the IC chip C1, the sidesubstantially perpendicular to the arrangement direction D1 andpositioned most closely to the input switch SW1 (region 10) will becalled a side L4. Among the four sides of the IC chip C1, the sidesubstantially perpendicular to the arrangement direction D1 andpositioned most closely to the output switch SW2 (region 20) will becalled a side L5. The sides L2 and L4 are disposed on the same side (theleft side in FIG. 2) of the power amplifier module M1. The sides L3 andL5 are disposed on the same side (the right side in FIG. 2) of the poweramplifier module M1.

FIG. 3 illustrates the positional relationship of ground surfaces and aground layer to the other components of the power amplifier module M1. Aground surface G1 is formed between the input switch SW1 (region 10) andthe output switch SW2 (region 20) on one of the two main surfaces of theIC chip C2. More specifically, the ground surface G1 is formed on themain surface (back surface, for example) of the IC chip C1 which is incontact with the substrate 100. A ground surface G2 is formed on one ofthe two main surfaces of the IC chip C1. More specifically, the groundsurface G2 is formed on the main surface (back surface, for example) ofthe IC chip C2 which is in contact with the substrate 100. A groundlayer G3 is buried in the substrate 100. The ground surfaces G1 and G2are electrically connected to the ground layer G3 through a via-hole(not shown).

In the power amplifier module M1 according to the first embodiment, theinput switch SW1 (region 10), the output switch SW2 (region 20), and thecontrol circuit CU (region 30) are integrated into the single IC chipC1, thereby eliminating the need to connect these components by usingwires or wiring provided on the substrate 100. Hence, fewer componentscan be mounted on the substrate 100, thereby reducing the size and thecost of the power amplifier module M1. The control circuit CU (region30) is formed between the input switch SW1 (region 10) and the outputswitch SW2 (region 20), so that it can suppress electromagnetic couplingbetween the input switch SW1 (region 10) and the output switch SW2(region 20), thereby making it possible to secure a sufficient level ofisolation therebetween. As a result, unwanted oscillation of the poweramplifier module M1 can be reduced. The IC chip C2 is disposed betweenthe input matching circuit MN1 and the inter-stage matching circuit MN2(region 40) and the output matching circuit MN3 (region 50), therebymaking it possible to secure a sufficient level of isolationtherebetween. Additionally, the input switch SW1 (region 10), the inputmatching circuit MN1 (region 40), and the inter-stage matching circuitMN2 (region 40) are disposed on the same side of the power amplifiermodule M1. The output switch SW2 (region 20) and the output matchingcircuit MN3 (region 50) are disposed on the same side of the poweramplifier module M1, thereby enhancing the isolation effect. The groundsurface G1 is formed between the input switch SW1 (region 10) and theoutput switch SW2 (region 20) on the back surface of the IC chip C1,while the ground surface G2 is formed on the back surface of the IC chipC2, thereby enhancing the isolation effect. The ground layer G3connected to the ground surfaces G1 and G2 can be formed so as to beinterposed between the components of the power amplifier module M1, inparticular, between the input matching circuit MN1 and the inter-stagematching circuit MN2 (region 40) and the output matching circuit MN3(region 50), as viewed from a direction substantially perpendicular tothe mounting surface of the substrate 100. This configuration canfurther enhance the isolation effect. A signal path for allowing an RFsignal to pass therethrough is indicated by the long dashed dotted linesSL1 in FIG. 3. In contrast to the configuration of the related art inwhich the individual components forming the power amplifier module M1are discretely disposed, it is possible to minimize the length of thesignal path SL1 in the power amplifier module M1 according to the firstembodiment, thereby reducing the insertion loss.

FIG. 4 illustrates the layout of individual components forming a poweramplifier module M2 according to a second embodiment. The poweramplifier module M2 is different from the power amplifier module M1 ofthe first embodiment in that it includes an IC chip C3 instead of the ICchips C1 and C2. The relationships concerning the connecting state amongthe components of the power amplifier module M2 is the same as those ofthe first embodiment shown in FIG. 1.

In FIG. 4, the driver-stage amplifier PA1 is disposed in a region 60,and the output-stage amplifier PA2 is disposed in a region 70. The inputswitch SW1 (region 10), the output switch SW2 (region 20), the controlcircuit CU (region 30), the driver-stage amplifier PA1 (region 60), andthe output-stage amplifier PA2 (region 70) are integrated into thesingle IC chip C3. The IC chip C3 is flip-chip mounted on the substrate100 and is disposed between the input matching circuit MN1 and theinter-stage matching circuit MN2 (region 40) and the output matchingcircuit MN3 (region 50). For the sake of representation, the wiring forconnecting each of the IC chip C3, the input matching circuit MN1, theinter-stage matching circuit MN2, and the output matching circuit MN3 isnot shown.

The control circuit CU (region 30) is disposed between the input switchSW1 (region 10) and the output switch SW2 (region 20). The driver-stageamplifier PA1 (region 60) and/or the output-stage amplifier PA2 (region70) are disposed between the input switch SW1 (region 10) and thecontrol circuit CU (region 30). The control circuit CU (region 30) isdisposed between the output switch SW2 (region 20) and a set of theinput switch SW1 (region 10), the driver-stage amplifier PA1 (region60), and the output-stage amplifier PA2 (region 70). Among the foursides of the IC chip C3, the side positioned most closely to the inputswitch SW1 (region 10) and the driver-stage amplifier PA1 (region 60)will be called a side L6, and the side positioned most closely to theoutput-stage amplifier PA2 (region 70) will be called a side L7. Thesides L6 and L7 oppose each other.

FIG. 5 illustrates the positional relationship of a ground surface and aground layer to the other components of the power amplifier module M2. Aground surface G4 is formed on one of the two main surfaces of the ICchip C3. More specifically, the ground surface G4 is formed on the mainsurface (back surface, for example) of the IC chip 3 which is in contactwith the substrate 100. A ground layer G5 is buried in the substrate100. The ground surface G4 and the ground layer G5 are electricallyconnected to each other through a via-hole (not shown).

In the power amplifier module M2 according to the second embodiment, theinput switch SW1 (region 10), the output switch SW2 (region 20), thecontrol circuit CU (region 30), the driver-stage amplifier PA1 (region60), and the output-stage amplifier PA2 (region 70) are integrated intothe single IC chip C3, thereby eliminating the need to connect thesecomponents by using wires or wiring provided on the substrate 100.Hence, fewer components can be mounted on the substrate 100, therebyreducing the size and the cost of the power amplifier module M2. In thesecond embodiment, even fewer components can be mounted on the substrate100 than those in the first embodiment, thereby making it easier toflip-chip mount the IC chip C3 on the substrate 100 than the IC chips C1and C2 on the substrate 100. The ground surface G4 is formed on the backsurface of the IC chip C3, thereby making it possible to secure asufficient level of isolation between input and output signals. Theground layer G5 connected to the ground surface G4 can be formed so asto be interposed between the components of the power amplifier moduleM2, in particular, between the input matching circuit MN1 and theinter-stage matching circuit MN2 (region 40) and the output matchingcircuit MN3 (region 50), as viewed from a direction substantiallyperpendicular to the mounting surface of the substrate 100. Thisconfiguration can further enhance the isolation effect. A signal pathfor allowing an RF signal to pass therethrough is indicated by the longdashed dotted lines SL2 in FIG. 4. In contrast to the configuration ofthe related art in which the individual components forming the poweramplifier module M2 are discretely disposed, it is possible to minimizethe length of the signal path SL2 in the power amplifier module M2according to the second embodiment, thereby reducing the insertion loss.

FIG. 6 illustrates the layout of individual components forming a poweramplifier module M3 according to a third embodiment. The power amplifiermodule M3 is different from the power amplifier module M2 of the secondembodiment in the relative positional relationships between the regions10 and 60 and between the regions 40 and 50. The relationshipsconcerning the connecting state among the components of the poweramplifier module M3 is the same as those of the first embodiment shownin FIG. 1. In the third embodiment, as well as in the second embodiment,a ground surface G4 is formed on the IC chip C3, and a ground layer G5is buried in the substrate 100. The ground surface G4 and the groundlayer G5 are electrically connected to each other through a via-hole(not shown). For the sake of representation, the wiring for connectingeach of the IC chip C3, the input matching circuit MN1 (region 40), theinter-stage matching circuit MN2 (region 40), and the output matchingcircuit MN3 (region 50) is not shown. The power amplifier module M3 willbe described below mainly by referring to the points different from thepower amplifier module M2 of the second embodiment, and a detailedexplanation of the same points will be omitted.

The input switch SW1 (region 10) is disposed between the controller CU(region 30) and the driver-stage amplifier PA1 (region 60) and/or theoutput-stage amplifier PA2 (region 70). For the sake of description, thedirection in which the driver-stage amplifier PA1 (region 60), the inputswitch SW1 (region 10), the control circuit CU (region 30), and theoutput switch SW2 (region 20) are arranged will be called an arrangementdirection D2. Among the four sides of the IC chip C3, the sidesubstantially parallel with the arrangement direction D2 and positionedmost closely to the output-stage amplifier PA2 will be called a side L8.Among the four sides of the IC chip C3, the side substantiallyorthogonal to the side L8 and positioned most closely to thedriver-stage amplifier PA1 (region 60) will be called a side L9. In thiscase, the output matching circuit MN3 (region 50) is disposedsubstantially parallel with the side L8 and is positioned most closelyto the side L8 among the four sides of the IC chip C3. The inputmatching circuit MN1 and the inter-stage matching circuit MN2 (region40) are disposed substantially parallel with the side L9 and arepositioned most closely to the side L9 among the four sides of the ICchip C3.

In the power amplifier module M3 according to the third embodiment, thewiring for input signals and that for output signals can be formed intwo directions substantially orthogonal to each other, thereby securinga sufficient level of isolation between input and output signals. Asignal path for allowing an RF signal to pass therethrough is indicatedby the long dashed dotted lines SL3 in FIG. 6. In contrast to theconfiguration of the related art in which the individual componentsforming the power amplifier module M3 are discretely disposed, it ispossible to minimize the length of the signal path SL3 in the poweramplifier module M3 according to the third embodiment, thereby reducingthe insertion loss.

FIG. 7 illustrates the layout of individual components forming a poweramplifier module M4 according to a fourth embodiment. The poweramplifier module M4 is different from the power amplifier module M1 ofthe first embodiment in that it does not include the input switch SW1.The relationships concerning the connecting state among the componentsof the power amplifier module M4 is the same as those of the firstembodiment shown in FIG. 1. The power amplifier module M4 will bedescribed below mainly by referring to the points different from thepower amplifier module M1 of the first embodiment, and a detailedexplanation of the same points will be omitted.

The output switch SW2 (region 20) and the control circuit CU (region 30)are integrated into a single IC chip C4. The driver-stage amplifier PA1and the output-stage amplifier PA2 are integrated into a single IC chipC5. For the sake of representation, the wiring for connecting each ofthe IC chips C4 and C5, the input matching circuit MN1 (region 40), theinter-stage matching circuit MN2 (region 40), and the output matchingcircuit MN3 (region 50) is not shown. For the sake of description, thedirection in which the control circuit CU (region 30) and the outputswitch SW2 (region 20) are arranged will be called an arrangementdirection D3. Among the four sides of the IC chip C5, the sidesubstantially parallel with the arrangement direction D3 and positionedmost closely to the IC chip C4 will be called a side L10. Among the foursides of the IC chip C5, the side positioned most closely to the inputmatching circuit MN1 (region 40) and the inter-stage matching circuitMN2 (region 40) will be called a side L11. Among the four sides of theIC chip C5, the side positioned most closely to the output matchingcircuit MN3 (region 50) will be called a side L12. The sides L11 and L12oppose each other with the side L10 interposed therebetween. Among thefour sides of the IC chip C4, the side substantially perpendicular tothe arrangement direction D3 and positioned most closely to the controlcircuit CU (region 30) will be called a side L13. Among the four sidesof the IC chip C4, the side substantially perpendicular to thearrangement direction D3 and positioned most closely to the outputswitch SW2 (region 20) will be called a side L14. The sides L11 and L13are disposed on the same side of the power amplifier module M4 (the leftside in FIG. 7). The sides L12 and L14 are disposed on the same side ofthe power amplifier module M4 (the right side in FIG. 7).

In the power amplifier module M4 according to the fourth embodiment, theoutput switch SW2 (region 20) and the control circuit CU (region 30) areintegrated into the single IC chip C4, thereby eliminating the need toconnect these components by using wires or wiring provided on thesubstrate 100. Hence, fewer components can be mounted on the substrate100, thereby reducing the size and the cost of the power amplifiermodule M4. The IC chip C5 is disposed between the input matching circuitMN1 and the inter-stage matching circuit MN2 (region 40) and the outputmatching circuit MN3 (region 50), thereby securing a sufficient level ofisolation therebetween. Additionally, the input matching circuit MN1(region 40) and the inter-stage matching circuit MN2 (region 40) aredisposed on the same side of the power amplifier module M4, while theoutput switch SW2 (region 20) and the output matching circuit MN3(region 50) are disposed on the same side of the power amplifier moduleM4, thereby securing a sufficient level of isolation between input andoutput signals. A signal path for allowing an RF signal to passtherethrough is indicated by the long dashed dotted lines SL4 in FIG. 7.In contrast to the configuration of the related art in which theindividual components forming the power amplifier module M4 arediscretely disposed, it is possible to minimize the length of the signalpath SL4 in the power amplifier module M4 according to the fourthembodiment, thereby reducing the insertion loss.

FIG. 8 illustrates the layout of individual components forming a poweramplifier module M5 according to a fifth embodiment. The power amplifiermodule M5 is different from the power amplifier module M4 of the fourthembodiment in that it includes an IC chip C6 instead of the IC chips C4and C5 included in the power amplifier module M4. The relationshipsconcerning the connecting state among the components of the poweramplifier module M5 is the same as those of the first embodiment shownin FIG. 1.

The driver-stage amplifier PA1 (region 60), the output-stage amplifierPA2 (region 70), the control circuit CU (region 30), and the outputswitch SW2 (region 20) are integrated into a single IC chip C6. For thesake of representation, the wiring for connecting each of the IC chipC6, the input matching circuit MN1 (region 40), the inter-stage matchingcircuit MN2 (region 40), and the output matching circuit MN3 (region 50)is not shown. The IC chip C6 is flip-chip-mounted on the substrate 100.The control circuit CU (region 30) is disposed between the output switchSW2 (region 20) and a set of the driver-stage amplifier PA1 (region 60)and the output-stage amplifier PA2 (region 70). Among the four sides ofthe IC chip C6, the side positioned most closely to the output-stageamplifier PA2 (region 70) and the output matching circuit MN3 (region50) will be called a side L15. Among the four sides of the IC chip C6,the side positioned most closely to the driver-stage amplifier PA1(region 60), the input matching circuit MN1 (region 40), and theinter-stage matching circuit MN2 (region 40) will be called a side L16.The sides L15 and L16 oppose each other.

In the power amplifier module M5 according to the fifth embodiment, theoutput switch SW2 (region 20), the control circuit CU (region 30), thedriver-stage amplifier PA1 (region 60), and the output-stage amplifierPA2 (region 70) are integrated into the single IC chip C6, therebyeliminating the need to connect these components by using wires orwiring provided on the substrate 100. Hence, fewer components can bemounted on the substrate 100, thereby reducing the size and the cost ofthe power amplifier module M5. In the fifth embodiment, even fewercomponents can be mounted on the substrate 100 than those in the fourthembodiment, thereby making it easier to flip-chip mount the IC chip C6on the substrate 100 than the IC chips C4 and C5 on the substrate 100.The IC chip C6 is disposed between the input matching circuit MN1 andthe inter-stage matching circuit MN2 (region 40) and the output matchingcircuit MN3 (region 50), thereby securing a sufficient level ofisolation between input and output signals. A signal path for allowingan RF signal to pass therethrough is indicated by the long dashed dottedlines SL5 in FIG. 8. In contrast to the configuration of the related artin which the individual components forming the power amplifier module M5are discretely disposed, it is possible to minimize the length of thesignal path SL5 in the power amplifier module M5 according to the fifthembodiment, thereby reducing the insertion loss.

FIG. 9 illustrates the layout of individual components forming a poweramplifier module M6 according to a sixth embodiment. The power amplifiermodule M6 is different from the power amplifier module M5 of the fifthembodiment in the relative positional relationship between the regions40 and 50. The relationships concerning the connecting state among thecomponents of the power amplifier module M6 is the same as those of thefirst embodiment shown in FIG. 1. Among the four sides of the IC chipC6, the side positioned most closely to the driver-stage amplifier PA1(region 60), the input matching circuit MN1 (region 40), and theinter-stage matching circuit MN2 (region 40) will be called a side L17.The sides L15 and L17 are substantially orthogonal to each other.

In the power amplifier module M6 according to the sixth embodiment, thewiring for input signals and that for output signals can be formed intwo directions substantially orthogonal to each other, thereby securinga sufficient level of isolation between input and output signals. Asignal path for allowing an RF signal to pass therethrough is indicatedby the long dashed dotted lines SL6 in FIG. 9. In contrast to theconfiguration of the related art in which the individual componentsforming the power amplifier module M6 are discretely disposed, it ispossible to minimize the length of the signal path SL6 in the poweramplifier module M6 according to the sixth embodiment, thereby reducingthe insertion loss.

FIG. 10 illustrates the configuration of a power amplifier module M7according to a seventh embodiment. The power amplifier module M7 isdifferent from the power amplifier module M1 of the first embodiment inthat it includes plural duplexers DPX1, DPX2, DPX3, and DPX4 and anantenna switch ANT-SW. The antenna switch ANT-SW includes terminals P51,P52, P53, and P54 connected to the duplexers DPX1, DPX2, DPX3, and DPX4,respectively, and also includes an antenna terminal P55 connected to anantenna ANT. The antenna switch ANT-SW selectively establishes a signalpath between one of the plural terminals P51, P52, P53, and P54 and theantenna terminal P55 so as to selectively connect one of the pluraloutput signal paths Tx1, Tx2, Tx3, and Tx4 to the antenna terminal P55.The control circuit CU controls the switching operation of the antennaswitch ANT-SW.

The duplexer DPX1 separates an RF signal (transmit signal) input intothe duplexer DPX1 via the output signal path Tx1 and an RF signal(received signal) input from the terminal P51 of the antenna switchANT-SW to the duplexer DPX1. Likewise, the duplexers DPX2, DPX3, andDPX4 separate transmit signals and received signals from each other. Thereceived signals subjected to filtering performed by the duplexers DPX1,DPX2, DPX3, and DPX4 pass through received signal paths Rx1, Rx2, Rx3,and Rx4, respectively.

FIG. 11 illustrates the layout of individual components forming thepower amplifier module M7 according to the seventh embodiment. Theantenna switch ANT-SW is disposed in a region 80. The duplexers DPX1,DPX2, DPX3, and DPX4 are disposed in regions 91, 92, 93, and 94,respectively. The driver-stage amplifier PA1 (region 60), theoutput-stage amplifier PA2 (region 70), the input switch SW1 (region10), the output switch SW2 (region 20), the control circuit CU (region30), and the antenna switch ANT-SW (region 80) are integrated into asingle IC chip C7. For the sake of representation, the wiring forconnecting each of the IC chip C7, the duplexer DPX1 (region 91), theduplexer DPX2 (region 92), the duplexer DPX3 (region 93), the duplexerDPX4 (region 94), the input matching circuit MN1 (region 40), theinter-stage matching circuit MN2 (region 40), and the output matchingcircuit MN3 (region 50) is not shown. The IC chip C7 isflip-chip-mounted on the substrate 100. The IC chip C7 is disposedbetween a set of the duplexer DPX1 (region 91) and the duplexer DPX2(region 92) and a set of the duplexer DPX3 (region 93) and the duplexerDPX4 (region 94). The control circuit CU (region 30) is disposed betweenthe input switch SW1 (region 10) and the output switch SW2 (region 20).A ground surface G6 is formed between the output switch SW2 (region 20)and the antenna switch ANT-SW (region 80) on one of the two mainsurfaces of the IC chip C7. More specifically, the ground surface G6 isformed on the main surface (back surface, for example) of the IC chip C7which is in contact with the substrate 100. A ground layer G7 is buriedin the substrate 100. The ground surface G6 and the ground layer G7 areelectrically connected to each other through a via-hole (not shown). Therelative positional relationships among the input switch SW1 (region10), the output switch SW2 (region 20), the control circuit CU (region30), the driver-stage amplifier PA1 (region 60), and the output-stageamplifier PA2 (region 70) is substantially the same as that in the thirdembodiment, and a detailed explanation thereof will thus be omitted.

In the power amplifier module M7 according to the seventh embodiment,the driver-stage amplifier PA1 (region 60), the output-stage amplifierPA2 (region 70), the input switch SW1 (region 10), the output switch SW2(region 20), the control circuit CU (region 30), and the antenna switchANT-SW (region 80) are integrated into the single IC chip C7, therebyeliminating the need to connect these components by using wires orwiring provided on the substrate 100. Hence, fewer components can bemounted on the substrate 100, thereby reducing the size and the cost ofthe power amplifier module M7. The control circuit CU (region 30) isformed between the input switch SW1 (region 10) and the output switchSW2 (region 20), so that it can suppress electromagnetic couplingbetween the input switch SW1 (region 10) and the output switch SW2(region 20), thereby securing a sufficient level of isolationtherebetween. As a result, unwanted oscillation of the power amplifiermodule M7 can be reduced. The ground surface G6 is formed between theoutput switch SW2 (region 20) and the antenna switch ANT-SW (region 80),thereby enhancing isolation therebetween. The ground surface G6 formedon the back surface of the IC chip C7 is connected to the ground layerG7 formed in the substrate 100, thereby securing a sufficient level ofisolation between the output switch SW2 (region 20) and the antennaswitch ANT-SW (region 80). The ground layer G7 connected to the groundsurface G6 can be formed so as to be interposed between the componentsof the power amplifier module M7, in particular, between the region 40and the regions 91 and 92 and between the region 50 and the regions 93and 94, as viewed from a direction substantially perpendicular to themounting surface of the substrate 100. This configuration can furtherenhance the isolation effect. A signal path for allowing an RF signal topass therethrough is indicated by the long dashed dotted lines SL7 inFIG. 11. In contrast to the configuration of the related art in whichthe individual components forming the power amplifier module M7 arediscretely disposed, it is possible to minimize the length of the signalpath SL7 in the power amplifier module M7 according to the seventhembodiment, thereby reducing the insertion loss.

To distinguish the IC chips C1 through C7 from each other, the IC chipCi may be called the i-th IC chip (i is an integer of 1 to 7). Todistinguish the sides L1 through L17 from each other, the side j may becalled the j-th side (j is an integer of 1 to 17). To distinguish theground surfaces G1 and G2 from each other, the ground surface G1 may becalled a first ground surface, and the ground surface G2 may be called asecond ground surface.

The above-described embodiments are provided for facilitating theunderstanding of the disclosure, but are not intended to be exhaustiveor to limit the disclosure to the precise forms disclosed. Modificationsand/or improvements may be made without necessarily departing from thespirit and scope of the disclosure, and equivalents of the disclosureare also encompassed in the disclosure. That is, suitable design changesmade to the embodiments by those skilled in the art are also encompassedin the disclosure within the spirit and scope of the disclosure. Forexample, the elements and the positions thereof of the embodiments arenot restricted to those described in the embodiments and may be changedin an appropriate manner.

While embodiments of the disclosure have been described above, it is tobe understood that variations and modifications will be apparent tothose skilled in the art without necessarily departing from the scopeand spirit of the disclosure. The scope of the disclosure, therefore, isto be determined solely by the following claims.

What is claimed is:
 1. A power amplifier module comprising: anoutput-stage amplifier; a driver-stage amplifier that is connected to aninput of the output-stage amplifier; an input switch configured toselectively connect one of a plurality of input signal paths to an inputof the driver-stage amplifier; an output switch configured toselectively connect one of a plurality of output signal paths to anoutput of the output-stage amplifier; and a control circuit configuredto control the input switch, the output switch, the driver-stageamplifier, and the output-stage amplifier, wherein: the output switchand the control circuit are integrated into a first integrated circuit(IC) chip, and within the first IC chip, the control circuit isphysically arranged adjacent to the output switch.
 2. A power amplifiermodule comprising: an output-stage amplifier; a driver-stage amplifierthat is connected to an input of the output-stage amplifier; an inputswitch configured to selectively connect one of a plurality of inputsignal paths to an input of the driver-stage amplifier; an output switchconfigured to selectively connect one of a plurality of output signalpaths to an output of the output-stage amplifier; and a control circuitconfigured to control the input switch, the output switch, thedriver-stage amplifier, and the output-stage amplifier, wherein: theinput switch and the control circuit are integrated into a firstintegrated circuit (IC) chip, and within the first IC chip, the controlcircuit is physically arranged adjacent to the input switch.
 3. Thepower amplifier module according to claim 1, wherein: the driver-stageamplifier and the output-stage amplifier are integrated into a second ICchip according to an arrangement direction, and the control circuit andthe output switch are arranged according to the arrangement direction.4. The power amplifier module according to claim 2, wherein: thedriver-stage amplifier and the output-stage amplifier are integratedinto a second IC chip according to an arrangement direction, and thecontrol circuit and the input switch are arranged according to thearrangement direction.
 5. The power amplifier module according to claim1, further comprising: a substrate for mounting the first IC chip,wherein a first ground surface is formed on a main surface of the firstIC chip that is in contact with the substrate.
 6. The power amplifiermodule according to claim 2, further comprising: a substrate formounting the first IC chip, wherein a first ground surface is formed ona main surface of the first IC chip that is in contact with thesubstrate.
 7. The power amplifier module according to claim 1, wherein:the driver-stage amplifier and the output-stage amplifier are integratedinto a second IC chip, the power amplifier module further comprises asubstrate for mounting the first IC chip and the second IC chip, a firstground surface is formed on a main surface of the first IC chip that isin contact with the substrate, a second ground surface is formed on amain surface of the second IC chip that is in contact with thesubstrate, and the first ground surface and the second ground surfaceare connected to each other.
 8. The power amplifier module according toclaim 2, wherein: the driver-stage amplifier and the output-stageamplifier are integrated into a second IC chip, the power amplifiermodule further comprises a substrate for mounting the first IC chip andthe second IC chip, a first ground surface is formed on a main surfaceof the first IC chip that is in contact with the substrate, a secondground surface is formed on a main surface of the second IC chip that isin contact with the substrate, and the first ground surface and thesecond ground surface are connected to each other.